We actually wanted to use that scheme for more new API paths, lets
see if it is really fitting starting with this.
Use the new widget-toolkit submitUrl helper to add the ID on create.
And unify the edit/create window creation, which may fit better in a
separate commit, it's quite small and was to cumbersome to untangle,
so just go against my one rules here... :(
Signed-off-by: Thomas Lamprecht <t.lamprecht@proxmox.com>